<!--[if IE 6]>
    <link type="text/css" rel="stylesheet" href="ie6.css" media="screen" />
    <script type="text/javascript" src="js/DD_belatedPNG_0.0.8a-min.js"></script>
    <script>
      DD_belatedPNG.fix('.element with png, #elements with png');
    </script>
<![endif]-->

http://www.dillerdesign.com/experiment/DD_belatedPNG/

Start with a basic IE6 conditional comment. Add the javascript inside for IE6. Pay close attention to the parent child structure. If the image is by itself, include the parent element; example: "#element img".

IE6 PNG Fix using DD_belatedPNG with supporting repeated background

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